Analysis: When will the terrible Texas drought end?

A couple of weeks ago I reported on the possibility of the current drought plaguing Texas extending into next summer. This is because of the 50 percent probability that La Niña will redevelop after this fall, bringing another dry winter to the state of Texas.

With this in mind, now that we’re into fall, I asked ImpactWeather‘s Fred Schmude for his thoughts on the drought persisting for awhile. He responded with a long, and thoughtful answer, which I’ve attached below as a guest blog entry. It’s worth reading in its depressing entirety.

A question many people are raising right now is when will the current intense drought end?

Before we answer that question we really need to figure out what caused the current dry spell and see if there are any changes forecast for the near or distant future. The drought really intensified last winter thanks in large part to a very strong La Niña over the eastern Tropical Pacific. La Niñas typically result in a weaker than normal sub tropical storm track limiting the amount of rain producing weather disturbances that affect the Texas area during a normal winter.

For this year that phenomena started in February and intensified during March and April with very few rain producing weather systems. By the later part of spring and early summer the La Niña phenomena weakened and became a non player, however the very dry soil over the Texas region intensified the drought and allowed a semi-permanent upper-level high pressure to build over the area keeping most of the rain bearing tropical disturbances either south or east of the Texas Gulf Coast. As a result, most of Texas was left high and dry resulting in the current 20-25 inch rain deficit we are currently experiencing in the Houston area and the increased fire danger as wildfires quickly spread across central and east Texas.

Unfortunately the main players that caused the very intense drought last winter are coming back this winter in the form of another potential La Niña condition. We currently are favoring a redeveloping moderate to strong La Niña this winter based largely on another weather phenomena called the Pacific Decadal Oscillation, or PDO. The PDO is a large scale weather cycle over the northern Pacific Ocean which demonstrates alternating periods of cold and warm cycles, which can typically last 10 to 20 years. When the PDO is in its cold phase La Niñas typically are more frequent and intense while the reverse is true during the warm phase of the PDO. For this year the PDO has shifted toward the negative phase, which is signaling a redeveloping La Niña later this fall as colder than normal water over the eastern Pacific Ocean is funneled southward into the eastern Tropical Pacific.

As a result, we should see the current drought persist through next spring over most of Texas, including the greater Houston area as La Niña intensifies. Yes, Texas will likely see some welcomed wet periods at times during the fall and early winter as the polar storm track occasionally shifts south bringing quick bursts of precipitation associated with cold fronts and other fast moving disturbances; however, below to well-below-normal precipitation will likely by the dominant weather trend over most of the state though next May.We can always hope for some type of a weak tropical system during the latter half of September into October, but even that scenario is looking less likely with time.

By the way our three driest years on record in the Houston area occurred in 1917 (17.66”), 1988 (22.93”) and 1901 (27.09”). In a normal year the Houston area will typically receive around 45.00 to 50.00” of rainfall, so you can see in 1917 we had a little more than third of the normal rainfall while in 1988 we had roughly half. This year we have currently tallied 11.00” for the year, while we should be at 32.58”, meaning so far this year we have received only about a third of our normal rainfall and are on a pace to tie or unfortunately surpass the all time 1917 record.

As temperatures run hot, the city of Houston runs a significant rain defecit. (National Weather Service)

And in case you’re wondering what was going on in the eastern Pacific Ocean in 1917, there was a strong La Niña in place along with a negative phase of the PDO. Yes, it’s indeed amazing how history repeat itself, not only in life but with the weather.

UPDATE: Several readers, including Zack, have asked how dry soil contributes to furthering our hot and dry summer, as Fred mentioned above. Here’s his answer:

That’s a great question and can be best answered by a rule of thermodynamics that basically states dry soil heats up faster than wet soil. The reason being is when moisture is evaporated out of wet soil cooling results since evaporation is a cooling process. Dry soil does not have that same benefit and as a result with the near absence of significant evaporation (a cooling process) the air will tend to heat up faster.

Why is this important in regards to pressure? Well, in the world of weather pressure drops off more rapidly with height in cold air and more slowly with height in warm air. Since the soil has been so dry and warm over Texas the past 6 months the end result is a tendency for higher pressure aloft (~500 millibars or 18,000 feet) to sit over the Lone Star State, which creates a sinking and stable environment limiting clouds and rain bearing weather systems.

In essence I blame the dry soil for the most intense part of the drought we are now experiencing. The dry soil has a direct feedback on the strength and endurance of the upper high that is parked over Texas. We need a nice soaking rain that will moisten the ground over a large part of Texas and change the weather pattern for the late fall, winter and especially next spring. If the soil does not moisten up, we could easily see that strong upper high build right back over the area for next spring.

Great question Dean. I’d be interested to know when and how the 1917 drought ended. If history repeats itself then by knowing how and when the 1917 drought ended maybe we can have a little insight as to when our current drought might actually end.

Thanks for the article link. I did some web digging. I haven’t had enough time to sort through things but I’m finding lots of information and comparisons to 1917-1918 and the mid-1950s but I’m not seeing anything discussing how either one ended. At this point, I can only presume they ended with some sort of weather pattern shift yielding more rain rather than anything tropical. That’s going to take some more digging. If anyone knows how either of these droughts ended (shift with rain or tropical weather), I would be interested to know.

Thanks for the article link. I did some web digging. I haven’t had enough time to sort through things but I’m finding lots of information and comparisons to 1917-1918 and the mid-1950s but I’m not seeing anything discussing how either one ended. At this point, I can only presume they ended with some sort of weather pattern shift yielding more rain rather than anything tropical. Does anybody have any leads as to how it ended? I sure don’t like the thought of a multi-year drought.

Eric, I love your blog, but you’ve got to stop with the depressing news. Is there anything anyone can do? Cloud seeding? Rain dance? Shutting Rick Perry up??? J/K. But seriously – how long does this La Nina and PDO normally last? Is two years normal? Should we expect some relief in 2012??

Hi Lisa. Hang in there! These blogs get me worked up too sometimes but I have to keep reminding myself it’s like leaving notes to somebody on the bathroom stall in grade school. Hope you have a good day!

not to worry Lisa, President Perry just had a national prayer event last month..and from my experience God is always quick to answer.. suddenly and without warning, he will answer.. sometimes we get to much;
I did, when I was first filled with the Holy Ghost.. but as an american I am greedy for more of that good stuff..

“…however the very dry soil over the Texas region intensified the drought and allowed a semi-permanent upper-level high pressure to build over the area keeping most of the rain bearing tropical disturbances either south or east of the Texas Gulf Coast.”

Scott, it is not a typo. It is the 2nd or 3rd time Fred (or some expert) has mentioned this on Eric’s blog. I have yet to understand how soil moisture can help create and keep a large high pressure system over the region. It appears to deal with some type of positive feedback loop.

When the area becomes so arid of all the moisture leaving the ground, you have no humidity and convection to start thunderstorm formation, thus rain. Furthermore, the drier it gets, the hotter the soil, thus the air and temperature gets and you have hot, sinking air [classic hi-pressure system feature]. With hot sinking air, the pressure rises, forget any chances of rain, thus a hi-pressure system. this is just the opposite of a low pressure system/hurricane where when the pressure drops, you keep getting a more intense, stronger storm. we all know what rain comes from a hurricane or low pressure system. How this cycle gets reversed is beyond me, but once it is started, it is insidious…

Any predictions on the temps this winter? Are we going to see the upper-teens/low-20′s for a 3rd year in a row? After this heat and drought I hope we at least are spared from another winter of hard freezes.

They may be correct in this development, but I’ll not put any stock into it just yet. I can’t count on one hand the number of times that the forecast showed good chances of rain this summer for a week to 10 days out, and it never came through. That probably happened 8-10 times over the last 3 months. How in the world can we predict what the next 6 months will bring? or a year?

I’m not saying they’re wrong, because I could guess at the weather for next year and say either “generally dry, or, extremely wet”, and I’d have a 50% chance of being right. I don’t like long range forecasting for that reason, it can get everyone all fired up one way or the other. Stop with the “here’s the weather for the next 12 months” predictions please.

I remember very few times thinking there might be rain on the horizon. 30% chance = wear sunscreen. 40% chance = we’re pretty unsure how it’s going to play out. even 60% is little better than even odds.

Or are you so rain-desperate that you’ll take 50/50 as “good chances”?

I look at weather.com EVERY day, and they have a 10 day forecast. More than 5 times this summer, in looking at that forecast, there were rain chances of 40% or greater predicted in the 10 day. As that day would approach, the chances every day would diminish, my son and I talked about it this all the time as he watched it on his phone too. And yes, 40% is a good chance, particularly when you’ve only been seeing 10% or less.

Yep, I agree Eric, which is my point exactly about this long range forecasts. I don’t gripe about weather predictions, I understand the variances that occur. But because there is such variance in just 10 day models, the thought of predicting overall development months and months out seems to be pointless, particularly for people to start saying as a result of said predictions, that we are in trouble. It’s a prediction, and 10 day predictions are many many times wrong, so this would be even more pointless.

Keep up the good work, I do like your columns and read them as often as possible.

I wonder if Rick Perry ever stopped to think that the drought could be a plague sent by the Lord to punish Texas for the way our state government treats the poor and God’s creation (a.k.a. “the environment”)?

SlimChance, you’ll never understand climate change sitting around with all your Lib buddies discussing how horrible everyone else is to destroy the earth as we know it. We don’t need complainers and conspirist on this blog. Use some common sense !!!!!

Eric, you’re alot like Ben Bernanke. We hear from you alot, but it’s never good. Ben’s lower for longer is equivalent to your accounts of no end in sight for the current drought. At least you would actaually something if you could. Ben lurks the drought in the financial markets with a box of matches.

I understand how some long-term predictions can be made and I’m also confident were in a cyle that potentially last for several years. What I want to know is the impact on the Houston area if this cycle repaets in both 2012 and 2013. It is not out of the question. However, I do question the ability for the city to make it through this – if indeed this drought lasts for another few years. There’s only so much water in the reserves and lakes. That is their worst-case back-up plan, which they are using now. But what happens when lake conroe and lake Houston run nearly dry — or too low to pump water from…

Some may say that this is all doom and gloom but I believe were in the beginning of the largest natural disaster in history. So much so that if this drought is continuing by June 2012, I do plan on and will move my family out of Houston and to another state. Some may think the weather guys are playing this up when in fact I believe that they are very much playing this down. I personally believe that a time will come witting 2 or so years that you will have no running water at your home and there will be no water to put out simple house fires. It’s just a simple but very unfortunate longterm weather trend. I am sure millions will be forced to move out of Houston due to now water by sometime in 2013.

i don’t believe things are going to be that dire, however i do think we will change the way we live. our concern with green lawns and water intense landscaspes will become a thing of the past. it amazes me how we have taken water for granted. we will adjust and cope with mother nature, we have no choice.
if you think it is dry here, drive thru the hill country. devastated.

i still can’t believe we have had 11 inches of rain. i know it is measured in one spot, but that is over an inch a month. i think we went over 5 months with less than 1/4 inch at any one time. i live on the southwest side, and don’t think we have come close to that number. are there any unofficial measurements taken anywhere else in houston.

Justbob, search around for your closest Wunderground-reporting independent station. You can do this via their map interface and clicking the icons to push through to the raw station data, where you’ll find daily, monthly, and yearly summaries. I’m in north Galveston County, where we had the marginal benefit of a couple of extremely isolated cloudbursts near the coast. Our nearest station is actually reporting 15.95 inches on the year, which is more than the “official” Houston number.http://www.wunderground.com/wundermap/

Eric, tanks for this interesting analysis. Bleak prospects for Texas, indeed. However, in my humble opinion, you failed to address an important issue – climate change. How much does global warming contribute to this epic drought/heat wave and all the other weather extremes we’re seeing worldwide in the past couple of years?

Going back to the Civil War, multi-year drouths in Texas have a mid-year on about a 22-year frequency. In recent times, that’s the ’30s, ’50s and a luck-out in the ’70s. Mid-’90s and now, here we are, worrying.

Actually, in all seriousness, that makes sense. When we moved here 4 years ago I was amused at the serially stubborn attempts to grow things that really don’t like to grow here…xeriscaping is the way to go, whatever one’s politics.

Why would you tear up your yard and put down gravel like “desert communities” because of a 1 year drought? Texas normally has PLENTY of rain to support what ever you want to grow, and it will again. This is a temporary pattern….

One of the tools the state uses to determine weather patterns is the study of the rings of cypress trees. Their data says we are in year 7 of a 20 year dry period. Modern record keeping seems to agree with that. While we might have some periods of wetter years. It seems the 20 year drought cycle is probably right.

We’ve seen that the dry conditions turn the whole state into a fire trap. If we don’t get rain, these fires that are breaking out in rural areas will start to threaten small and medium-sized cities. The areas around Austin are choked with smoke. I saw the Bastrop fire on Monday from about 15 miles away. It looked like a huge storm moving in when there wasn’t a cloud in the sky.

Check with your county AgriLife Extension Agency about XeroScaping and EarthKind. There are ways to keep your landscape relatively nice during drought seasons. One way is to plant Texas natives which can tolerate the dry conditions. Other ways are with drip irrigation and mulching. Horticulturist Doug Welsh (Texas A&M) has a book out called Texas Garden Almanac (2007) which has the best info and lots of recommendations of what we need to do to maintain our lawns and gardens. As a master gardener, I highly recommend it.

[...] SciGuy is saying that the drought might extend into Summer of 2012. I really, really, really hope he is wrong! Analysis: When will the terrible Texas drought end? | SciGuy | a Chron.com blog [...]

It is humorous the way we who have reservations about HUMAN CAUSED climate change are called every name related to stupid, i.e. moron, retarded,ignorant, redneck,uneducated, STUPID, hillbillies, etc. Yet they will never argue that while the Arctic is losing ice, the Antarctic is gaining ice at a rate faster than the northern polar cap is losing it. Nor will they respond to the SCIENTIFIC evidence (drill plugs) that point to faster periods of global climate change BEFORE man made his entrance on the old planet Earth. Guess we STUPID REDNECKS will remain that way till you Gore sheep, eh, followers can offer CONVINCING evidence to prove your point. Saying something repeatedly does not make it true. While I am all for getting off our reliance on carbon fuels, & all for saving trees & whales & animals, I am in it for different reasons. Global HUMAN OVERPOPULATION is a greater current threat. And one that needs to be addressed NOW.

[...] a comment (0) Go to comments ImpactWeather StormWatch Manager Fred Schmude weighs in today on SciGuy Eric Berger’s blog with the cryin’ shame not-so-great news that much of the south-central U.S. might not see any [...]

Apparently, land ice is decreasing…and decreasing at a rapid rate due to global warming. Sea ice is increasing for a variety of reasons, one of which may be that increased moisture levels are leading to increased snowfall which, when landing upon sea ice, pushes the sea ice down deeper so that more ocean water is exposed to freezing temperatures.

Since official weather records for Galveston go back farther than Houston’s (all the way to 1871), any clue on what is the driest year the Island City has experienced? I would surmise, barring a storm, both cities would share similar rainfall patterns in history…

***It is humorous the way we who have reservations about HUMAN CAUSED climate change are called every name related to stupid, i.e. moron, retarded,ignorant, redneck,uneducated, STUPID, hillbillies, etc. ****

Because that’s what you are.

What is your degree in? Is it in a climate change field, like geophysics? Physics? Geology?

What peer-reviewed papers have you written on the subject?

Did you know that the science is argued in the peer-reviwed literature, not in the opinion pages, or pulled out of the rear end of whatever conservative moron you deem an authority who has ZERO qualifications or education much less expertise in the relevant fields?

If you had cancer, who would you want to treat you: an MD who graduated at the top of every class, who had specifically trained to treat cancer, and who had substantial experience in the field? Or some hillbilly who think he’s some kind of expert because he read an article about it on the internet? If you were a General or Admiral and had a delicate but essential military mission you needed to accomplish, would you send in a bunch of kids fresh out of basic training, or would you send Delta Force or the Seals? If you were charged with murder, would you hire a kid who hasn’t passed the bar or even gone to law school, or would you find out a defense lawyer who went to law school, passed the bar, and had won numerous cases just like yours?

When you say that you don’t accept the scientific consensus about climate change, moron, you are essentially saying that you would hire the moron who wasn’t qualified to practice law, or you’d send in the inexperienced recruits to a dangerous and important mission, or you’d have the hillbilly who has zero training, zero knowledge and zero expertise treat your cancer.

People who reject expert advice and counsel, people who reject experience and knowledge and training–like you do–are correctly deemed MORONS.

Worse, you climate-change denying MORONS are arrogant about the fact that you rely on questionable, ignorant sources, that it makes your ignorance equal to the KNOWLEDGE and EXPERIENCE of your betters.

If you’re merely called moron, hillbilly & etc, it’s better than you deserve.

I think it’s ALL Bush’s fault! Or is it God is upset at who is in the whitehouse now? I think since the fires are Perry’s fault and the tsunami in the Phillipines was Bush’s fault, the drought here in Texas is Obama’s fault. hahaha

I totally agree with TXAqua. This just proves that weather runs in patterns. It’s just the way God created the earth. I live south of Corpus Christi. When Hermine was approaching the coast, we were excited. We were on the “good side” of a tropical system. But, the EYE was NOT in the center of the storm. So therefore, what little precipitation the that made it on shore was on the “dry side” of the storm. Since the land was so hot & dry, it totally sheered the top off the storm. We got a whopping 2/10′s of an inch of rain! The deep Rio Grand Valley received 7″ in some places!

Thank you Eric for the article. It was very informative. Albeit, very depressing and I hope that you’re not correct in your forecast. The deer population is probably going to be effected by this. I’m scared that some of the fawns will not have been strong enough and the does have enough nutrition to sustain 1 much less 2 fawns. I even had a new born calf die. We attributed it to the excessive heat. It looked healthy the day it was born. But we were awoke by the cow the next morning bellering for her calf. We found the calf later dead. If we run out of our hay supply that we were lucky enough to get after the rain in January, we are in bad shape! I’ll have to sell all my cattle. I will not let them starve and/or completely over graze my land.

Dad was a rice farmer here in the 50s so has an unusual recall of our past weather extremes. I have no idea about the meteorological reasoning for the end of the 1950s drought, but he once told me that we went from one extreme to the other with rains continuing until the Colorado and Brazos rivers nearly met.

Seems like a bit of a stretch to me…someone else may want to fact-check this one. Until then, I’m going with Dad.

Jacquelyne, I was thinking the same thing! Should we all throw some
ice out as well? Our native grass is not just dying, it’s disintergrating. We’ve had to sell 2/3 of our cattle; hay is getting scarce or very expensive. My crazy 83 year old aunt said she’d do a rain dance outside naked, if nothing else it’d scare the sun away!